Push-button operated devices



June 26, 1956 c. F. ROBBINS 2,752,440

PUSH-BUTTON OPERATED DEVICES Filed March 18, 1953 2 Sheets-Sheet l June26, 1956 c. F. ROBBINS 2,752,440

PUSH-BUTTON OPERATED DEVICES Filed March 18, 1953 2 Sheets-Sheet 2 I I 1I7 I 1 I I I I l. I I6 III I PUSH-BUTTON OPERATED DEVICES Clyde F.Robbins, Milwaukee, Wis., assignor to Cutler- Harnrner, Inc., Milwaukee,Wis., a corporation of Delaware Application March 18, 1953, Serial No.343,048

11 Claims. (Cl. 20044) This invention relates to improvements inpush-button operated devices and more particularly to push-button switchcontrol stations of the type capable of being padlocked in a givenposition.

The primary object of this invention is to provide for a push-buttonswitch a novel and simple latching means for latching of the push-buttonin any one of a number of different positions selectively.

Another object is to provide latching means of the aforementionedcharacter which is adaptable to one-hole mounted push-button stations.

Another object is to provide latching means of the aforementionedcharacter including a part located with a recess in one of the switchparts so as to be virtually unnoticeable and nonobst'ructive duringoperation of the switch.

Another object is to provide latching means of the aforementionedcharacter which automatically remains in either the latched or unlatchedposition, as desired.

A more specific object is to provide a switch latching means employingan over-center C-spring which is virtually concealed within certain ofthe switch parts.

Another specific object is to provide a switch latching means of theaforementioned character which is capable of receiving a padlock haspfor locking the switch in a given position.

The novel features which I consider characteristic of my invention areset forth with particularity in the appended claims. The device itself,however, both as to its organization and mode of operation, togetherwith additional objects and advantages thereof, will best be understoodfrom the following description of specific embodiments when read inconnection with the accompanying drawings, in which,

Fig. l is an enlarged top plan view of a push-button switch stationemploying the subject invention and showing the push-button padlocked inits downward position;

Fig. 2 is a substantially full size sectional view showing thepushbutton padlocked in its upward position and having a portion of theswitch housing broken away to show the stationary contacts and thebridging member; said sectional view being taken along the center line22 of Fig. 1;

Fig. 3 is a sectional view taken along the horizontal line 33 of Fig. 2showing the push-button in substantially full size and in its unlatchedposition;

Fig. 4 is a sectional view of a switch having modified mounting meansand showing the push-button in its latched position; and

Fig. 5 is a sectional view of a switch having another modified mountingmeans and showing the push-button in its latched position.

Like reference characters indicate corresponding parts throughout theseveral views of the drawings.

Referring to the drawings, they show a one-hole mounted push-buttonstation positioned on a mounting panel 1 and provided with latchingmeans to be hereinafter described. As shown in Fig. 2, the switchcomnited States Patent Q 2,752,446 Patented June 26, 1956 prisesstationary contact sets 2 and 3 and lower and upper bridging members 4.Said stationary contact sets 2 and 3 are adapted to be connected toelectrical circuits to be controlled as by means of suitable terminalmembers (not shown), whereas the bridging members 4 are attached to aswitch operating plunger 5. Said bridging members 4 are attached toplunger 5 by suitable spring means 6, so that the plunger 5 can becontinued downwardly following initial contact of lower bridging member4 with stationary contact set 2, thereby permitting continued movementof plunger 5 without changing the relative position of said lowerbridging member 4 and said set 2.

Said plunger 5 is also biased upwardly by means (not shown) independentof the previously mentioned spring 6, so that it will automaticallyreturn to its upward position, shown in Fig. 2, when unlatched andreleased by the operator. Switch housing 7, which encloses the switchparts, is fastened as by means of bolts 8 to an adapter 9. Said adapter9 is provided so that said switch housing 7 can be easily mounted withina single hole 1 in a suitable mounting panel 1.

Said adapter is provided with threaded openings for receiving said bolts8 to thereby provide a rigid attachment between switch housing 7 andadapter 9. Said adapter 9 is also provided with a centrally disposedthreaded opening 9 of a diameter slightly smaller than the opening 1 inpanel 1. As shown in Fig. 2 said threaded opening 9 of adapter 9 isengaged by a threaded reduced end portion 10 of a bushing 11). Saidbushing 10 is also formed with an enlarged end portion 16 and an opening10 extending throughout its entire length. Between the reduced endportion 14 and the enlarged end portion 119 is an annular shoulder 10Also in engagement with said reduced end portion 10* is a mounting nut11 having a threaded opening 11 and formed with an annular shoulder 11'.Bushing 10 and mounting nut 11 are each formed with knurling at 10 and11, respectively, to facilitate manual assembly and adjustment of saidthreaded members.

Positioned between mounting nut 11 and panel 1 is a positioning plate 12formed with a downwardly extending tongue portion 12 and, as shown inFig. 1, said tongue portion 12 of plate 12 extends into a small opening1 in panel 1. Positioned between panel 1 and adapter 9 is a gasket 13having therein a substantially centrally disposed opening 13 Said gasket13 is so positioned on adapter 9 with respect to the annular shoulder 9*(Fig. 2) as to prevent contact between said gasket 13 and the threadedreduced end portion 10 of bushing 10 and consequent excessive wearing ofthe former. Said annular shoulder 9* also prevents excessive compressionof said gasket 13 while providing for firm mounting of the switchregardless of whether or not a gasket is utilized. Said gasket 13 isalso provided with a small opening for receiving tongue portion 12 ofplate 12 and provides the desirable resiliency for firmly fastening theswitch to the panel. it also provides an oil-tight seal for protectingthe switch parts against the detrimental effects of oil. Adapter 9 isalso formed with a small opening or recess (not shown) for receivingtongue portion 12 of plate 12 and is thereby prevented from rotatingrelative to panel 1 when said parts are in assembled position.

Slidably movable within opening 10 of bushing 11) is the plunger 5having its upper end shaped to provide a manually operable push-button.As is believed apparent. the downward movement of plunger 5 will effectengagement between stationary contact set 2 and the lower bridgingmember 4, while release of said plunger will effect disengagement of set2 and engagement of said upper bridging member 4 with contact set 3.

Under certain circumstances it becomes very desirable, if not essential,to insure against operation of the switch after the latter has beenoperated to a particular position. That is, such an arrangement isdesirable to provide a safe place for maintenance personnel to work onmachines controlled by the particular switch or to prevent interruptionof a necessarily continuous operation. Toward such end this inventionprovides means for latching the plunger in a given position or, further,providing for padlocking thereof in any such given position.

As shown in the drawings, the latching-locking feature comprises alatching member 14 formed with a tongue portion 14 a main body portion14 and an upturned portion 14. The main body portion 14 of latch member14 is pivotally positioned in a slot 1i) in bushing 10 (see Fig. 2).Such pivotal positioning is elfected by means of a pin 15 which is pressfitted into suitable openings in bushing 10 but which loosely andpivotally engages said main body portion 14. As shown in the drawings,the tongue portion 14 main body portion 14 and the upturned portion 14are shaped .in accordance with the curvature of bushing 10. That is, theupturned portion 14 is shaped so as to lie closely against the knurledportion 10 of bushing 10 when in an unlatched position. Tongue portion14 and main body portion 14' are shaped to permit unobstructed movementof plunger when latching member 14 is in its unlatched position.

As shown in Fig. 1, tongue portion 14 is adapted to engage the upperportion of plunger 5 to maintain the plunger in its downward position.Plunger 5 is also formed with an annular groove 5 to receive said tongueportion 14 and thereby maintain said plunger in its upward position, asshown in Fig. 2; or in any predetermined intermediate position,depending upon the location of said groove 5 with respect to the upperend of plunger 5. Also it is believed to be apparent that groove 5 mightalternatively be formed to any desired width, thereby permitting limitedmovement of plunger 5 and providing operation of a given set of contactswhile keeping the other set of contacts in a predetermined opened orclosed position throughout such limited operation of plunger 5. It isthus possible to modify existing switches as desired to obtain any oneof several types of switch operations.

Bushing is also provided with an annular groove 10 as shown in thedrawings. Positioned within said annular groove is a C-spring 16 asshown in Fig. I. Said bushing 10 is also provided with a radial opening10 which communicates with said annular groove 10 as shown in Fig. I.Said radial opening 19 receives and positions one end of said C-spring16 while the other end thereof engages main body portion 14 of latchingmember 14. The portion of spring 16 intermediate its ends is positionedmore or less within the annular groove 10* of bushing 10. Theabove-mentioned engagement be tween spring 16 and latching member 14provides an over-center spring arrangement whereby said C-spring 16maintains said latching member 14 in its latched or unlatched positionas desired. Said latching member 14 is maintained by spring 15 in itsunlatched position by virtue of abutting contact between the end of mainbody portion 14 and bushing 10 or by contact between the upturnedportion 14 of latching member 14 and the knurled portion 10 of bushing10. Said latching member 14 is maintained by spring 16 in its latchedposition by virtue of contact between the end of upturned portion 14 andsaid knurled portion 10 of bushing 10, as shown in Fig. 1.

As shown in Fig. 3 the ends of spring 16 are arranged to provide a forcetoward each other along lineX-X when latching member 14 is in itsunlatched position. I This force along line XX will. maintain saidlatching member 14 in such unlatched position due to the rotationaleffect thereof on said member 14. When member 14 is opened or placed inits latched position, such direction of the force of spring 16 coincideswtih line YY in Fig. 1. Thus the rotational force of spring 16 asapplied to member 14 will be shifted to the other side of pin 15 therebymaintaining said latching member 14 in its latched position. Thereforesaid latching member 14 will remain in either its unlatching or latchingposition due to the force of said C-spring irrespective of whether ornot plunger 14 exerts a force on tongue portion 14 of latching member14. As will be understood, the hasp of an ordinary padlock may beinserted into and locked in the opening in the upturned portion 14 oflatching member 14 to prevent movement of the plunger 5 in an upwarddirection (in Fig. l) or in either direction (in Fig. 2).

The modification shown in Fig. 4 employs the above explainedlatching-locking feature mounted in bushing 17 .in a manner alsoheretofore explained. The primary purpose of this modification is toprovide a sleeve member 18 of such length as to prevent the plunger 5from extending beyond the end thereof to thereby render the same lesssusceptible to accidental or nnintential switch operation.

As shown, sleeve 18 is formed with external threads for threadedlyreceiving said bushing 17. A mounting nut 19 formed with an internalthread for engagement with the external threads on said bushing 17 isprovided to rigidly secure the switch to the mounting panel 1. The lowerperipheral edge of said sleeve 18 is flanged as at 18 Positioned betweensaid flange 18 and the mounting panel 1, is a resilient gasket 13.Positioning plate 12 is inserted between said mounting plate and themounting nut 19.

In order to permit positioning of the latching-locking feature atvarious desirable positions around said plunger 5, said sleeve 18 isformed with several slots 18, for slidably receiving the tongue portion14 latching member 14. Such engagement between tongue portion 14 and aslot 18 provides a tamper-proof arrangement while padlocked in suchposition. That is, such engagement would prevent substantial relativemovement between bushing 17 and sleeve 18 thereby insuring againstremoval of the latching-locking feature without first removing thepadlock.

The modification of Fig. 5 shows a means for providing an ordinaryswitch with a bushing 20 constructed with the novel latching-lockingfeature of the present invention. In this arrangement the bushing 20threadedly engages sleeve 21 thereby serving the dual purpose of rigidlyholding the switch structure to the amounting panel 1 and also carryingthe locking member 14. As will be understood, the bushing 20 is notinherently susceptible of being positioned for the convenience ofoperating latch- .ing member 14, but must necessarily be positioned soas to effect secure mounting of the switch. A certain amount offlexibility can be attained by varying the thickness of gasket 13 or byemploying several gaskets as shims as shown in Fig. 5.

It will be apparent that this latching-locking means can be applied toand successfully used with any plunger operated mechanism. Morespecifically, it is realized that this invention can be used inconjunction with any desired switch arrangement; that is, any number ofn0rmally open contacts and/or any number of normally closed contactswith latching and locking ability in any desired position.

Although I have shown and described certain specific embodiments of myinvention, I am fully aware that many modifications thereof arepossible. My invention, therefore, is not to be restricted exceptinsofar as is necessitated by the prior art and by the spirit of theappended claims.

I claim:

1. The combination with a device having an operating pushdiutton, of alatching member pivotally positioned relative to said push-button andcapable of engaging said button to positively prevent movement thereoffrom a given normal operative position thereof or alternatively engagingsaid button to retain the same in a different position, and over-centerC-spring means in engagement with said latching member to maintain saidlatching member engaged with or disengaged from said button as desired.

2. The combination with a device having an operating push-button, of alatching member pivotally positioned relative to said push-button andcapable of engaging said button to positively prevent movement thereoffrom a given normal operative position thereof or alternatively engagingsaid button to retain the same in a diiferent position, and over-centerC-spring means in engagement with said latching member to bias saidmember in either pivotal direction selectively, thereby biasing saidmember into or out of controlling engagement with said button asdesired.

3. The combination with a device having an operating push-button, of alatching member pivotally positioned relative to said push-button andcapable of engaging said button to prevent movement thereof, and aC-spring anchored at one end and in engagement with said latching memberat its other end to bias said member in either pivotal directionselectively, thereby biasing said member into or out of engagement withsaid button as desired.

4. The combination with a device having an operating push-button, of alatching member pivotally positioned relative to said push-button andcapable of engaging said button to prevent movement thereof, over-centerC-spring means in engagement with said latching member to maintain saidlatching member engaged with or disengaged from said button as desired,and means on said latching member for receiving a padlock hasp toprevent disengagement of said latching member from said button.

5. The combination with a device having an operating push-button, of abushing formed with an opening for slidably receiving said push-button,a manually operated latching member pivotally positioned on said bushingand adapted for pivotal movement into engagement with said button tothereby prevent movement of the latter, and C-spring means havingopposite ends thereof respectively engaged with said latching member andsaid bushing to thereby bias said latching member in either pivotaldirection selectively, to thereby bias said member into or out ofengagement with said button as desired.

6. The combination with a device having an operating push-button, of abushing formed with an opening for slidably receiving said push-button,a latching member pivotally positioned on said bushing and capable ofengaging said button when pivoted to thereby prevent movement thereof,and spring means at least partially recessed within said bushing and inengagement with said latching member and said bushing to bias saidmember in either pivotal direction selectively, to thereby bias saidmember into or out of engagement with said button as desired.

7. The combination with a device having an operating push-button, of abushing formed with an opening for receiving said push-button and formedwith an annular groove, a latching member pivotally positioned on saidbushing and capable when pivoted of engaging said button to therebyprevent movement of the latter, and a C-spring at least partiallyrecessed within said annular groove and engaging said member and saidbushing to bias said member in either pivotal direction selectively.

8. The combination with a device having an operating push-button, of abushing formed with an opening for receiving said push-button and formedwith an annular groove, a latching member pivotally positioned on saidbushing and capable when pivoted of engaging said button to therebyprevent movement of the latter, a C-spring at least partially recessedwithin said annular groove and engaging said member and said bushing tobias said member in either pivotal direction selectively, and means onsaid latching member for receiving a padlock hasp to preventdisengagement of said latching member from said button.

9. The combination with a device having an operating push-button, of abushing formed with an opening for receiving said push-button and formedwith an annular groove, a latching member pivotally positioned on saidbushing and capable when pivoted of engaging said button to therebyprevent movement thereof, a C-spring at least partially recessed withinsaid annular groove and engaging said member and said bushing to biassaid member in either pivotal direction selectively, and means on saidlatching member for receiving a padlock hasp to prevent disengagement ofsaid latching member from said button, said last mentioned means havinga shape corresponding to at least a portion of the contour of saidbushing and being juxaposed with respect thereto when disengaged fromsaid push-button.

10. In combination, an electric switch having an operating push-buttonmovable rectilinearly, means to make and break an electric circuit to becontrolled, said means being operated by said push-button to make andbreak said circuit selectively, a bushing formed with an opening forreceiving said push-button and formed with an annular groove, a latchingmember pivotally positioned on said bushing and capable when pivotallymoved of engaging said button to thereby prevent movement of the latter,a C-spring at least partially recessed within said annular groove andengaging said member and said bushing to bias said member in eitherpivotal direction selectively, and means on said latching member forreceiving a padlock hasp to prevent disengagement of said latchingmember from said button.

11. In a one-hole mountable push-button switch station, an electricswitch having an operating push-button movable rectilinearly, means tomake and break an elec tric circuit to be controlled, said means beingoperated by said push-button to make and break said circuit selectively,a bushing formed with an opening for slidably receiving said push-buttonand also formed with a slot and an annular groove, a latching memberpivotally positioned within said slot and capable when pivotally movedof engaging said push-button to thereby prevent movement of the latter,a C-spring at least partially recessed within said annular groove andengaging said member and said bushing to bias said member in eitherpivotal direction selectively, means on said latching member includingan opening for receiving a padlock hasp to prevent disengagement of saidlatching member from said button, said last mentioned means having ashape corresponding to at least a portion of the contour of said bushingand being juxtaposed with respect thereto when disengaged from saidpush-button, and means for mounting said station in one hole of amounting panel, said last mentioned means including a positioning platefor preventing relative movement between said switch and said mountingpanel.

References Cited in the file of this patent UNITED STATES PATENTS1,285,093 Fishel Nov. 19, 1918 2,370,877 Robbins Mar. 6, 1945 2,659,780Berger Nov. 17, 1953 2,673,259 Appleton et a1 Mar. 23, 1954

